I have 4 chicks that are somewhere between 7 and 10 days old. They have been in a brooder with pine shavings and I have fed medicated starter. 2 days ago I gave them a clump of grass and dirt/rocks/sand from the yard which they pulled several worms out of. Only just today was I able to get to the feed store for chick grit. When I pick them up I can notice the area where the crop is feels full. Its isnt super noticeable just by looking at them, only when you feel it. They dont seem to be uncomfortable. Is this normal or should I be worried? Thanks!!